Answer:
Step-by-step explanation:
let 7 + 3√2 be an rational number where
7+3√2 = a/b [ a and b are coprime and b is not equal to zero]
3√2= a/b-7
3√2 =( a-7b) /b
√2 = (a-7b) /3b .....(i)
Now ,from equation (i) ,we get that √2 is rational but we know that √2 is irrational. so actually 7 + 3√2 is irrational not rational. thus our assumption is wrong. The number is irrational.
17. 2/3
18. 1 1/9
20.9 1/11
21. 2 909/100 (closest i could get)
Hope I helped and hope you had a good day!
Answer:
First find what the sale price of the CD is. 30% off means the CD is selling for 70% of the original cost ( 100%-30% = 70%)
Multiply the original cost by 70%:
17.00 x 0.70 = $11.90 ( sale price)
Now you need to multiply the sale price by the tax percentage to find the amount of tax:
11.90 x 0.08 = 0.95 ( tax)
Now add the sale price and the tax for the total cost:
11.90 + 0.95 = $12.85